I have a variety of spreadsheets that I need to narrow down to one population.

There is one massive spreadsheet that contains the majority of information on all spreadsheets.

There are several smaller spreadsheets that contain information that sometimes overlaps what is in the massive spreadsheet.

I want to remove all the overlapping information from the smaller spreadsheets from the massive spreadsheet.

In short, I want the massive spreadsheet to contain only unique lines that do not overlap with content in the other spreadsheets.

There is one identifying number that can be used for filtering or sorting - an ID of sorts.

Any ideas?